Cursor Click from Don Calaca replicates one of the earliest ever one-button games, played before most people had home computers. It took one or more pocket calculators that had a "constant calculations" mode, started by tapping in 1,+,+. You would then be able to hammer the equals button as fast as you could to constantly count upwards. With two players and two calculators you could both race to a set-number, e.g. first to 100 wins. The 1970s equivalent of Track and Field or Sonic and Mario at the Olympics.